相关实验视频
Updated: Jan 31, 2026

09:14
Cardiac Magnetic Resonance Imaging at 7 Tesla
Published on: January 6, 2019
12.3K
下一代7特斯拉动脉旋转标签与旋转螺旋获取使得3D大脑 perfusion和功能性MRI中mesoscale分辨率
Chenyang Zhao1, Fanhua Guo1, Zidong Yang1
1Laboratory of FMRI Technology (LOFT), Mark & Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
Magnetic resonance in medicine
|January 29, 2026
概括
7特斯拉的高分辨率全脑输液成像使用先进的ASL技术实现. 这种非侵入性方法与MRI和细胞成像相结合,揭示了详细的神经活动.
科学领域:
- 神经成像是一种神经成像.
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 生理学 生理学 生理学
背景情况:
- 先进的磁共振成像 (MRI) 技术对于理解高分辨率的大脑功能至关重要.
- 动脉旋转标签 (ASL) 提供非侵入性输液量化,但面临着分辨率限制.
研究的目的:
- 开发和验证一个高分辨率 (≤1mm同otropic) 的全脑 perfusion 成像技术.
- 利用下一代ASL脉冲序列,重建算法和MRI硬件来提高成像性能.
主要方法:
- 使用基于FLASH的伪连续ASL (pCASL) 序列与旋转金角螺旋堆 (rGA-SoS) 采样.
- 采用动态压缩传感 (CS) 重建与运动解析的自导航来增强时空分辨率.
- 在NexGen 7T扫描仪上集成了高密度阵列线圈和高性能冲动梯度.
主要成果:
- 实现了0.8mm的同位素空间分辨率和14s的时间分辨率在1mm的同位素,SNR增加了3.3倍.
- 在静止状态 perfusion 和组织学微血管/细胞体密度之间显示出强烈的相关性.
- 在手指敲击和工作记忆任务期间,在运动皮质中观察到明显的层状激活模式.
结论:
- 开发的方法提供了一个非侵入性的工具,可以将美苏镜MRI与显微镜细胞成像相结合.
- 允许调查神经刺激和抑制的基础正和负 fMRI 激活.
- 提高了以前所未有的分辨率详细研究大脑功能和结构的能力.
相关概念视频
Radiological Investigation II: MRI and Ventilation Perfusion Scan
605
Description
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
605
Light Acquisition
9.6K
In order to produce glucose, plants need to capture sufficient light energy. Many modern plants have evolved leaves specialized for light acquisition. Leaves can be only millimeters in width or tens of meters wide, depending on the environment. Due to competition for sunlight, evolution has driven the evolution of increasingly larger leaves and taller plants, to avoid shading by their neighbors with contaminant elaboration of root architecture and mechanisms to transport water and nutrients.
9.6K
NMR Spectroscopy: Spin–Spin Coupling
3.2K
The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved...
3.2K
Spin–Spin Coupling: One-Bond Coupling
1.5K
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
1.5K
Spin–Spin Coupling Constant: Overview
1.5K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.5K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
1.7K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.7K

